Trisetum melicoides

Plants perennial, with both fertile and sterile shoots; cespitose. Culms (20)40-80(100) cm, erect, smooth or scabridulous. Leaves concentrated below midlength on the culms; sheaths glabrous or pilose; ligules 1.5-3.5 mm, rounded or truncate; blades 10-20+ cm long, 2-9 mm wide, flat, lax. Panicles 8-20 cm long, usually 2-4 cm wide, lax, nodding, silvery-green or -tan; lower branches to 5 cm, ascending, naked below, the spikelets imbricate distally. Spikelets 5-7(9) mm, pedicellate, lance-ovate, with 2(4) florets; rachilla internodes and hairs 1.3-2 mm. Glumes unequal, widest at or below the middle; lower glumes 4-5.5 mm; upper glumes 5-7 mm long, nearly equaling the florets, wider than the lower glumes; callus hairs 1.5-2 mm; lemmas 5-6 mm, smooth or scabridulous, apices usually minutely bifid, sometimes entire, awns absent or to 2 mm, arising just below and rarely exceeding the apices; paleas shorter than the lemmas; anthers 0.6-0.8 mm. Caryopses about 3 mm, sparsely pubescent distally. 2n = 14.

Trisetum melicoides is a native species that grows in moist, cool stream banks, on gravelly shores, shaded rock ledges (especially calcareous ones), and in damp woods. It grows in southeastern Canada and the northeastern United States. It is listed as endangered in Wisconsin, New York, and Maine. Plants with pilose sheaths have been called T. melicoides var. majus (A. Gray) Hitchc., but the trait varies within populations.

Culms 4-8 dm, glabrous or scaberulous; sheaths usually glabrous; blades 3-6 mm wide, scaberulous or sparsely pilose; infl slender, 8-20 cm, the lower branches sometimes 5 cm; spikelets 2-fld or rarely with a much reduced third fl; glumes widest near or below the middle, scabrous on the keel only, the first 1-veined, 4-5.6 mm, the second 3 veined, 5-7 mm; rachilla-joints 1.3-2 mm, thickly beset with white hairs of about the same length; lemmas acute, undivided, awnless. Moist gravelly or rocky soil, usually in woods; Nf. and Que. to Ont., Mich., and Wis.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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